From Swedish Patent No. 7413157-4 (publ. no. 383959) a surgical suction device is previously known, which comprises a point aspirator and an outer aspiration tube arranged round the point aspirator, whereby the outer tube is axially displaceable in order to enable point aspiration or sump aspiration. The suction device is produced to enable alternative point or sump aspiration, i.e., aspiration in a limited area, or aspiration for removal of larger amounts of liquid from a greater area. This aspiration cannot be made to work twice in an atraumatic manner, and on aspiration tissue will be invaginated by suction adheration.
Use of the aspiration technique in surgical operations generally requires the establishment of an air pressure lower than the ambient pressure at a certain spot and thereby the achievement of a flow of air, liquid, tissue parts or other matter in a desired direction. The principle implies the establishment of a reduced pressure in a tube or a mouthpiece attached thereto, which is directed to the spot where aspiration is to take place. In a free open mouthpiece connected to a vacuum source a balance is rapidly established between flow rate and vacuum level.
On aspiration of a liquid however, a column of liquid will be built up, as air does not continuously reach the mouthpiece. The rapid movement of the liquid column in the tube causes a piston movement which by its force makes tissue adhere by suction and invaginate into the mouthpiece. Suction adheration frequently causes a trauma in the tissue, which trauma can be more or less serious depending on where it occurs, and which in any event is a damage to organs and body, which must be healed. Further, suction adheration means that the work in the wound area is impeded as the operator must eliminate the adheration with a special manipulation and force.